Page 181 - Fundamentals of Gas Shale Reservoirs

dIScuSSIOn 161

Well#2 Well#2
3
Stress/pressure (psi) Bulk density (g/cm )
3,000 5,000 7,000 9,000 11,000 13,000 1.95 2.15 2.35 2.55 2.75 2.95
2500 2500

2700 2700

Effective RHOB
stress
2900 PP_Son 2900 NPHI
OBPres
TVD (m) 3100 TVD (m) 3100

3300 3300

Kockatea shale
(3043–3714) m TVD
3500 3500

3700 3700
0.45 0.25 0.05 –0.15
Porosity (%)
FIGURE 7.24 Well log responses to overpressure across the Kockatea Shale (Perth Basin).

Well#8
Kockatea shale (2962–3185) m
NPOR-PHND (%) Well#8
2.8 0.35
3
GR (GAPI) DEPT PPG-Son (Psi/ft) RHOB (g/cm )
0. 250. (M) 0.3 0.8 1.95 2.95
NPOR-PHND (%)
2.7 Clay 0.45 –0.15 0.45 NPOR (%) –0.15
Cutoffs PHND (%)
0.3 0.45 –0.15
Sand
2.6 Shale
RHOB (g/cm 3 ) 2.5 0.25 2900

2.4 Illite-rich line 2950
0.2 3000
2.3
3050
Smectite-rich line
3100
2.2 0.15
40 60 80 100 120 140 3150
DT ( s/ft)

FIGURE 7.25 Sonic–density cross‐plots for Kockatea Shale for Well #8 (left), (neutron porosity–density porosity) is shown in color. Well logs
plot and pore pressure profile versus depth for Well #8 (right).